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Monday, June 29, 2009

I am still traveling, so posts will still be erratic until towards the end of July. I did catch an internet connection long enough to find a list of web articles you may want to follow up on.

The most important comes first, the first meeting of the Decadal Survey. I will be unable to listen in; if anyone does and writes up a summary, I'll post it here.

JULY DECADAL SURVEY MEETING WEBCASTING

The National Research Council's Planetary Science Decadal Survey willwebcast all of the open sessions during the 6-8 July meeting of itsSteering Group. The webcast will be available at the following URL:

Cost overruns have bedeviled planetary programs from multiple agencies, but they are not unique to planetary programs. The journal Science's blog discusses the cost overruns on the United State's next generation of polar weather/climate satellites. To put it simply, the program has become a disaster of diminishing expectations and increasing costs. Note that the new cost estimate for the program, $14B is greater than NASA's budget for a decade of planetary exploration.

Space.com has a long article on ESA and NASA's planned collaboration on the ExoMars mission. The current plans have NASA providing the launch vehicle for ESA's ExoMars rover and NASA's Mars Science orbiter. (The latter will focus on locating the sources of methane and other short-lived gases in the Martian atmosphere.) From the article, it sounds like there will have to be substantial engineering work to make this happen. The article also discusses why ESA and NASA will not be able to collaborate on a dark energy mission.

Wednesday, June 17, 2009

The BBC reports that two of ESA's planetary programs are experiencing cost overruns. In the case of ExoMars, the Humboldt surface station has been eliminated. While this was expected, its loss means that many measurements that would have been prototypes of a future Mars network mission have been eliminated. The article goes on to say that NASA will take on a significant role in the mission including providing the launch vehicle. The cooperation between ESA and NASA on Mars missions is expected to continue for a series of Mars missions.

In separate news, ESA's Bepi-Colombo mission is both over budget and over weight, requiring that that mission also undergo a slimming.

One of the contributors to Unmanned Spaceflight noted that a Congressional budget report expressed concern that the President's proposed budget (and most importantly its projected budgets for the coming years) doesn't seem to support funding the Jupiter Europa flagship mission:

"The Committee is concerned that the budget profile for the Outer Planets flagship mission to Europa appears inconsistent with a 2020 launch. Therefore, NASA is directed within 60 days of enactment of this Act to provide a projected full lifetime budget outline for the Europa mission, to include anticipated contributions from foreign partners, and an alternative budget profile that would accelerate the launch to 2018."

Editorial Thoughts: Planetary missions are getting more complex and more expensive now that so many of the easy missions have been completed. Cost overruns have always been a problem, but seem to me more likely as more difficult missions are tackled. This will make formulating a coherent roadmap all the more difficult.

The Congressional report seems to support my reading of the budget that there will not be enough funds to both support a large (~50% of NASA's planetary budget) Mars program, the Discovery and New Frontiers programs, and a large outer planets Flagship mission. The upcoming Decadal Survey process is going to be interesting, indeed.

I’m traveling for several weeks, so posts will be erratic. Fortunately, this appears to be a slow time for news on future planetary missions and roadmaps. One consequence of traveling is that I sometimes won’t be able to easily look up URLs to my source material. My apologies.

Editorial thoughts: Cowling says that the schedule slips are because of , “These slips are related to cost overruns that SMD is unable and/or unwilling to contain.” Cost overruns are certainly happening, but I think that the science division is also being run more conservatively. If you bet that shit will happen, you are less aggressive on your schedules. Some of the missions were so early in their definition (e.g., ILN and Solar Probe) that their schedules were place holders rather than firm commitments. And the schedule for the Mars sample return wasn’t credible before and, in my opinion still isn’t credible.

In a related note, the Decadal Survey has released a request for information as an early step to findr a company to provide independent cost assessments for proposed missions. According the RFP,

“The National Research Council (NRC), under sponsorship of the National Aeronautics and Space Administration (NASA) and the National Science Foundation (NSF), has established the Planetary Science Decadal Survey Committee (the Survey Committee)—consisting of a Steering Group and five supporting panels—to conduct the Planetary Science Decadal Survey (the Survey)to assess the key scientific questions for the field over the next decade and to identify the priority investments in spacecraft missions that will enable the field to address those questions (see Attachment B for the Survey Committee’s statement of task). To support this goal, the NRC intends to contract with an independent organization to estimate the cost of potential spacecraft missions to various destinations in the solar system. These cost estimates will be an input to the committee’s overall prioritization process.”

“The contractor shall perform objective, independent estimates of cost, risk and schedule for the various mission concepts which may be at significantly different levels of definition and development maturity. The technical data describing the mission concepts will be coming from several different institutions and/or individuals. The Survey Committee will not uncritically accept estimates provided by project proponents or responsible agencies. It is anticipated that, on the basis of the technical readiness assessment, the Survey Committee may decide that some activities may take the form of high-priority technology development programs rather than projects.”

“The contractor shall develop a series of top level quad-charts for each activity concept using four “quad” panels: a) activity description including technology development requirements, b) cost and schedule estimates, c) funding profile, and d) technology readiness and risk rating. The contractor shall also provide an “S-curve” that is generated by the cost model on a separate chart for the committee’s consideration. The quad-charts will provide a top-level snapshot of each concept for summary purposes and an overview of its merits, issues, and expected budgeting requirements. All information provided in the quad-charts is to be backed by additional analysis, provided to the committee by the contractor.”

Editorial Thoughts: I believe that independent cost and risk assessments are absolutely essential to develop a credible Decadal plan. However, I’ve been involved in a number of cost and schedule estimation exercises (for a leading high tech firm). If my experience there is any guide, this Decadal Survey will have more accurate cost and schedule estimates than the last, but the costs and schedules for at least some of the priority missions will still be low. Assuming that is the case, it would be valuable for the Survey to provide a descope plan to decide up front which missions will either be cancelled or will not be started as cost overruns occur.

Monday, June 8, 2009

The journal Nature has an article about how Mars has lost its special place in NASA's planetary program. For the last decade or so, the Mars program has received approximately 50% of NASA's planetary exploration budget. That has enabled a steady stream of missions that -- and I don't think this is hyperbole -- has revolutionized our understanding of the Red Planet. However, the Mars program has no special place in the Decadal Survey. In addition, small Mars missions must now compete against other planetary targets in the Discovery program instead of having their own Mars Scout line item.

A couple of good quotes:

"Before the Mars programme office was set up in 1994, individual missions had to round up Congressional support — the reason, says Christensen, why no Mars missions flew between the 1976 Viking landers and the 1992 Mars Observer, which failed to reach Mars. With a dedicated programme, missions can plan for the future in smaller steps."

"But the Mars community might have itself to blame for the tight budgets that have led to the current quandaries. The $2.3-billion Mars Science Laboratory — the super-sized rover scheduled for launch in 2011 — ended up being the mammoth, bells-and-whistles mission that a stepwise Mars programme was supposed to help avoid. The mission also ended up chewing through hundreds of millions of dollars in its budget overruns — more than enough to fund a Mars Scout."

Editorial Thoughts: I believe that the real decision of the Decadal Survey in progress will be whether to prioritize several medium to big missions to a number of planetary targets or to have a focus program that chews up a large portion of the budget leaving money for only a few modest missions to other targets. There are a number of high priority missions that fall into the approximately $1B class that is too small to be a Flagship mission but too large for the New Frontiers program. A comet sample return, a Mars Network mission, or an advanced Venus orbiter with a high resolution radar are all examples. The survey could prioritize three of these missions and still fund the Discovery ($425M) and New Frontiers ($650M). (All of this analysis assumes flat budgest adjusted for inflation.)

Or the Decadal Survey could prioritize one location. A continuation of a well funded series of Mars missions is one possibility. Funding the Jupiter Europa orbiter would be another. (My analysis of the budget says that both cannot be funded; I hope I'm mistaken.) In addition to this one focus target, the Discovery and New Frontiers programs could target modest missions to other locations in the solar system.

In a way, the champions of a continued focus on Mars have a speed bump in their path. The program is largely justified on exploring the past and current potential for life or habitable locations. The Curiousity rover (MSL) and ExoMars will directly test that possibility at two sites. Arguing for continued high levels of funding requires faith that the answers delivered by those rovers will not be a resounding, 'No'.

I personally believe that Mars exploration as a prioritiy can be justified by simply learning about another terrestrial world in depth. Another decade of missions will greatly expand our knowledge.

On the other hand, a continued focus on Mars seems to preclude either the Jupiter Europa orbiter or the Discovery and New Frontiers missions.

It will be interesting to see how the Decadal Survey choses among these options.

Saturday, June 6, 2009

The last Decadal Survey for planetary science produced a wealth of analyzes for scientific goals and possible missions. The inputs to the process were posted on the web and made for fascinating reading.

The schedule of meetings to generate input for the new Decadal Survey has been posted. It's a roadmap to when we can begin to read about the planetary communities ideas and priorities for exploration in the next decade.

This is the second part of an occasional series of blogs on planetary network missions. While planetary network missions have been proposed for decades, only one -- the lunar ALSEP stations left by the Apollo astronauts -- has ever been put in place. For a period in the late 1990s and early 2000s, the French CNES agency had an approved Mars network mission on its books. While the Netlander mission was eventually cancelled for budgetary reasons, the plans for that mission provide a comprehensive view of what a future network mission might look like.

Predicted areas of seismic activity on Mars.

Many characteristics of planets can be adequately characterized only with measurements from multiple locations on a planet's surface. Seismic measurements, for example, require simultaneous measurements from at least three locations to determine the location of the source event. Weather and climate measurements also require simultaneous measurements at multiple locations to understand the forces that drive patterns and responses to those patterns. Geodesy measurements to study subtle patterns in a planet's rotation for clues to the interior structure also are best performed from multiple surface stations.

While each of the Netlanders would have been small (more on that later), CNES packed an ambitious list of study goals into the mission. Among the global goals were:

Monitoring of seismic activity to characterize the structure of the core, mantle, and crust

Geodesy through measurements of precession, nutation, and obliquity

Meteorology measurements to enhance understanding of the climate

Measurements of the magnetic field to determine its origin and evolution

Study of the interaction of the ionosphere with the surface

Each lander would also characterize its landing site by:

Imaging of the landing site to study morphology and mineralogy

Detect subsurface reservoirs with ground penetrating radar

Study soil thermal and cohesion properties

The mass of each lander had to be kept small so that several could be carried. The design called for an entry and descent (parachutes and airbags) system of 44 kg and a landed station weight of 22 kg. The nine instruments would weigh only 6 kg.

After landing, a series of petals would open (and right the lander if it had landed upside down) exposing solar panels. Power was a major concern. While the designers hoped for 2 Earth years of operation, they were concerned that dust collecting on the solar panels would prematurely end the mission. (This was before the MER rover mission discovered that wind gusts would regularly clean solar panels.) Power available for the lander would be minimal: 50 Wh/sol (compare that with the several hundred Wh/sol for the MER landers).

Solar radiance levels and thermal concerns limited possible landing sites to near equatorial regions, while the parachute descent system limited landing sites to low lying areas. Three of the landers would be placed in a triangle with sides up to 1000 km. The fourth lander would be place at approximately the opposite side of the planet. The distribution of the landers was chosen to maximize the ability to locate the source of seismic events.

In addition to the landers, the carrier craft would enter Mars orbit to serve as a data relay. Each lander would produce about 100 Mb of data per week.

The design reflected a number of factors that any network mission must face. While more stations are always better to both provide greater sampling and redundancy, weight limits likely will keep the number of landers to a minimum. The small size of each lander will keep the area of any solar panels small, limiting power and the sophistication of the instruments and the amount of data they can produce. The data rates produced by the seismometer necessitates a relay orbiter (except for the moon, where stations on the near side can directly communicate with Earth).

In the next installment in this series, I’ll look at a design for a network mission that optimized the network for climate studies.

About Me

You can contact me at futureplanets1@gmail.com with any questions or comments.
I have followed planetary exploration since I opened my newspaper in 1976 and saw the first photo from the surface of Mars. The challenges of conceiving and designing planetary missions has always fascinated me. I don't have any formal tie to NASA or planetary exploration (although I use data from NASA's Earth science missions in my professional work as an ecologist).
Corrections and additions always welcome.